A new window can dramatically cut energy bills and give a home a fresh look. Before installing the replacement, you should do several things.
Using a level, check that the side jambs of the existing window are plumb. If they aren’t, screw wood shims by each pre-drilled hole to prop up the jambs.
Frame
The frame is the outer edge of the window opening, which provides a seal against moisture. Ensure that it’s free of paint, wood shavings and other debris before you install the new window. Apply an elastomeric caulk to the exposed inner face of exterior casings and blind stops at the top and sides of the frame.
Score trim boards where necessary to remove them without damaging the wall or existing trim. Score the area with a utility knife to break the old caulk and scrape it off with a wood putty blade.If you want to know more about replacing windows, visit this site adelphiaexteriors.com
Place the replacement window in the frame and loosely fasten it with partially driven screws through the lower left and upper right screw holes. Check the windows for plumb by running a level along its diagonal measurements from opposite corners. Shim the sides of the window as needed until the measurements match. Then, lightly stuff insulation in the cracks around the window. This will help prevent future bowing.
Glass
If the replacement window is too large for the opening, add 1 in (2.5 cm) furring strips along the side jambs to reduce the gap. Adding this insulation will also help protect against moisture intrusion, which leads to wood rot and mold.
Before installing the new glass pane, scrape away old paint and sand down the grooves to bare wood, coating them with a waterproof sealer. A heat gun may be used to soften any remaining putty. Then, replace the metal glazing points and lay a thin bead of latex caulk around the perimeter for a weather seal.
Place the new window and use a level to ensure it is square. Then, measure diagonally across the window from corner to corner and adjust it until the measurements are equal. Loosely fasten the window with screws through the lower left and upper right screw holes, allowing you to pull them out and readjust the window if necessary.
Trim
Working from the inside, set the window in the opening and screw it to the wall. If the window is too loose, use shims, plastic ones are preferable since they don’t mildew, to secure it in place. After the window is in, use expanding foam to fill any remaining gaps between the frame and the walls. This is particularly important for retrofit windows that don’t have a nail fin or new construction windows that go into a sheathing-free rough opening.
Reattach the interior stops around the outside of the frame and inside the sash rail. Then replace the parting stop, which is a strip of wood that runs along the top jamb and holds the sash lifts.
Remove the lower sash, cut the sash cords and unscrew the sash weight pulleys. Stuff the empty weight pockets with loosely packed fiberglass insulation to increase the energy efficiency of the window. Finally, reattach the sash and replace the exterior stops.
Insulation
A well-functioning window needs proper insulation. If there is any existing insulation in the old casing around a window, it should be removed, and replaced with a canned foam that is specially formulated for windows. If there are any gaps between the new insert window and the casing, seal them with elastomeric caulk on the inside, or use a foam-rubber backer rod on the outside.
Before installing the new window, vacuum debris from the sill and frame. Make sure that the frame is level and square. If it is not, insert wooden shims where necessary until the opening is perfectly square and plumb.
Remove the weight pockets on the sides of the window frames, cut away any sash cords and pulleys and discard them. On the inside, stuff insulating foam into the weight pockets and apply a small amount of exterior caulk to ensure that it remains in place. On the outside, run a line of caulk along the sill and header, and two vertical sides of the frame.